Thermodynamic assessments of the Bi–Lu and Lu–Sb systems

The phase diagrams and thermodynamic properties in the Bi–Lu and Lu–Sb binary systems have been assessed by using the CALPHAD (Calculation of Phase Diagrams) method on the basis of experimental data including the thermodynamic properties and phase equilibria. The Gibbs free energies of the liquid, hexagonal close-packed (hcp) and rhombohedral phases were described by the substitutional solution model, and the intermetallic compounds (Bi2Lu, BiLu, Bi3Lu5, Lu3Sb, Lu5Sb3, αLuSb, βLuSb and LuSb2 phases) were treated as stoichiometric compounds. The thermodynamic parameters of the Bi–Lu and Lu–Sb binary systems were obtained, and agreement between the calculated results and experimental data was obtained for each binary system.

► The Bi–Lu and Lu–Sb binary systems have been assessed by using the CALPHAD method. ► The Gibbs free energies of solution phases were described by the substitution solution model. ► The intermetallic compounds were treated as stoichiometric compounds. ► The thermodynamic parameters of the Bi–Lu and Lu–Sb binary systems were obtained. ► Agreement between the calculated results and experimental data was obtained for each binary system.